Hand paddle

ABSTRACT

The present invention is a swim aid consisting of a paddle blade having a hand side and an opposite water side, a proximal end, a distal end opposite the proximal end and having a distal edge and opposite first and second lateral ends. Finger apertures are formed along the distal end of the blade and separated from the distal edge by a fingertip portion, the apertures being separated from each other by inter-digital portions. The paddle includes a wrist portion formed on the proximal end of the blade, the wrist portion having a wrist strap, and a palm portion formed on the blade between the apertures and the wrist portion, the palm portion forming a concave surface on the waterside of the blade. A thumb notch is formed on the first lateral end of the blade. The paddle further includes a first and second flange portion formed on the first and second lateral ends, respectively, the flange portions being swept back from the water side of the blade towards the hand side of the blade, the first flange portion extending from the notch to the wrist portion, the second flange portion extending along the second lateral end from the wrist portion to the apertures. The inter-digital portions are swept back from the waterside of the blade towards the hand side of the blade and the fingertip portion is swept forward towards the waterside of the blade relative to the inter-digital portions sufficiently to permit the users&#39; fingers to extend fully through the apertures when the paddle is worn.

FIELD OF THE INVENTION

The invention relates generally to hand paddles for swimming.

BACKGROUND OF THE INVENTION

Swimming aids such as swim fins and hand paddles are routinely used bothas aids to swimming and as swim training aids. Hand paddles inparticular are useful as swimming aids since they permit the user toapply greater force to their swimming strokes. Traditionally, handpaddles for use in swimming consist of a blade worn on each of the usershands. In a majority of hand paddle designs, which have been attempted,the blade consists of a flat planar member roughly in the outline of ahand and having a strap or brace on one side of the blade foraccommodating the user's hand. For example, U.S. Pat. No. 894,311 toBrenton, U.S. Pat. No. 2,389,196 to Harmon, U.S. Pat. No. 2,555,969 toHolcombe, U.S. Pat. No. 3,765,042 to Montrella, U.S. Pat. No. 3,922,740to Potter, U.S. Pat. No. 4,913,418 to Schlueter et al., U.S. Pat. No.5,288,254 to Elson, U.S. Pat. No. 5,511,998 to Johnson, U.S. Pat. No.5,651,710 to Rives et al., and U.S. Pat. No. 6,019,650 to Rives et al.and many others all disclose swim paddles having flat planar swim bladeswith one or more straps for securing the paddle to the user's hand.Other swim paddles use a flat planar blade having a plurality ofapertures configured to permit the user to grasp onto the blade bypassing the user's fingers through the apertures to facilitate theuser's grip on the paddle. U.S. Pat. No. 2,745,119 to Whipple and U.S.Pat. No. 3,397,414 to Webb are examples of this sort of design. Yetanother design for swimming hand paddles consist of a flat blade havingan integral hand grip permitting the user to grip onto the paddle bygrasping the hand grip. U.S. Pat. No. 4,233,925 to Proctor, U.S. Pat.No. 4,493,662 to Richmond and U.S. Pat. No. 6,398,603 to Brown areexamples of this later design.

These prior art hand paddles all permit the user to apply greater forceto their swimming strokes; however, they suffer from a common problem,namely flutter. As the flat planar paddle is forced through the water bythe user, the paddle tends to flutter wildly causing the user to expendenergy to hold his hand steady through the stroke. Furthermore, thefluttering motion experienced by these flat planar swimming paddles maycause the user to loose his or her grip on the paddle. As a result, theuser must often tighten his or grip on the paddle in order to keep thepaddle in control during the stroke. A tighter grip creates increasedfatigue and muscle strain in the user's hand, as the user must exertadditional effort into maintaining a smooth swimming stroke.Furthermore, flat planar paddle designs usually require the users handto be held flat against the swimming paddle with the fingersoutstretched. This is not a natural position since the human hand, whenin a comfortable position, tends to cup. Holding the hand in a flatposition with the fingers outstretched for long periods of time resultsin increased hand strain and hand fatigue.

Swimming paddles having concaved paddles have been attempted. Theseswimming paddles usually include a blade having a concave surface on oneside and a hand holding aid, such as a hand strap, on the other side.U.S. Pat. No. 950,633 to Eastman, U.S. Pat. No. 2,159,972 to Larson andU.S. Pat. No. 183,045 to Dunlop and U.S. Pat. No. 5,643,027 to Evans etal. are examples of this type of design. These swim paddles consist of aflat member having a concave surface on one side and a convex surface onthe opposite side, the hand strap being incorporated on the convex side.These designs have the advantage of permitting the user to grip the handpaddle in a more comfortable manner. These concave paddle designs alsosuffer from the problems associated with paddle flutter. Indeed, theseconcave designs often suffer from increased flutter due to turbulencecreated by the concave surface impinging on the water.

SUMMARY OF THE INVENTION

In accordance with the present invention, here is provided a handswimming paddle which overcomes the drawbacks of the prior art such asflutter and hand strain. The improved hand paddle includes a bladehaving a hand side and an opposite waterside. The blade has a proximalend, a distal end opposite the proximal end and opposite first andsecond lateral ends. A wrist portion is formed on the proximal end ofthe blade, the wrist portion adapted and configured to retain a user'swrist when the paddle is worn. A finger portion is formed towards thedistal end of the blade, the finger portion being adapted and configuredto retain the user's fingers when the paddle is worn. First and secondflange portions are formed on the first and second lateral ends,respectively, the flange portions being swept back from the water sideof the blade towards the hand side of the blade, the flange portionsextending from the wrist portion to the finger portion of the blade.

The invention is also directed at a method of manufacturing a swimpaddle as described above by first forming a metal blade having theshape of the desired hand paddle by stamping a sheet of metal and thencoating the metal blade with a plastic material.

The invention is also directed at a method manufacturing a swim paddleas described above by first extruding a high modulus thermoplastic intoa foamed sheet of two to six thousands of an inch thick with a densityof 6 to 15 pounds per cubic foot, then thermoforming the sheet into aslightly concave geometric shape, then cooling and stress-stabilizingthe stress-stabilized sheet and then cutting out the paddle in a cutter.

With the foregoing in view, and other advantages as will become apparentto those skilled in the art to which this invention relates as thisspecification proceeds, the invention is herein described by referenceto the accompanying drawings forming a part hereof, which includes adescription of the preferred typical embodiment of the principles of thepresent invention.

DESCRIPTION OF THE DRAWINGS

FIG. 1. is a top view of a right hand swim paddle made in accordancewith the invention.

FIG. 2. is a sectional view of the swim paddle shown in FIG. 1 takenalong line A-A.

FIG. 3. is a sectional view of the swim paddle shown in FIG. 2 takenalong line B-B.

FIG. 4. is a top view of a right hand swim paddle made in accordancewith the invention being worn on a user's hand.

FIG. 5 is a sectional view of the swim paddle shown in FIG. 4 takenalong line C-C.

FIG. 6 is a bottom view of right hand swim paddle made in accordancewith the invention being worn on a user's hand.

FIG. 7 is a bottom view of the right hand swim paddle made in accordancewith the invention being worn on a user's hand with the user's fingersbeing extended.

In the drawings like characters of reference indicate correspondingparts in the different figures.

DETAILED DESCRIPTION OF THE INVENTION

Referring firstly to FIG. 1, a swim paddle made in accordance with theinvention for use on the right hand is shown generally as item 10. Itwill be appreciated that the present invention is directed towards swimpaddles for use with both the right and left hands. A swim paddle madein accordance with the present invention for use in the left hand wouldbe a mirror copy of paddle 10 and would have all of the features of thepaddle shown in FIG. 1. Paddle 10 consists of a blade 12 having a handside 14, a water side 16 on the opposite side of the hand side, proximalend 18, a distal end 20 opposite the distal end and opposite first andsecond lateral ends 22 and 24, respectively. Wrist portion 26 is formedon proximal end 18 of the blade, the wrist portion being formed anddimensioned to receive the wrist (not shown) of the user's right hand.Slits 28 and 30 are formed on wrist portion 26 to accommodate a wriststrap (not shown). The blade includes a finger portion 32 formed towardsdistal end 20. Apertures 34, 36, 38 and 40 are formed on finger portion32 adjacent distal end 20. Apertures 34 to 40 are dimensioned andconfigured to receive the fingers of the user's right hand (not shown).The blade further includes a palm portion 46 in the approximate centerof the blade between wrist portion 26 and finger portion 32 and flangeportions 42 and 44. Notch 48 is provided on first latter end 22 toaccommodate a user's thumb.

First and second flange portions 42 and 44, respectively, are formed onthe first and second lateral ends of the blade, respectively, on eitherside of wrist portion 26. As best seen in FIG. 2, first flange portion42 and second flange portion 44 are swept back from waterside 16 towardshand side 14 such that the flange portions extend upward relative towrist portion 26 between the flanges.

Referring back to FIG. 1, finger portion 32 includes inter-digitalportions 54, 55, 57 and 59. Fingertip portion 56 is formed on the bladebetween distal end 20 and apertures 34, 36, 38 and 40. As best seen inFIG. 3, the inter-digital portions are swept back from waterside 16towards hand side 14 and fingertip portion 56 is swept forward from thehand side towards the waterside of the blade. Palm portion 46 of theblade is shaped such that the palm portion forms a concave surface 50 onthe waterside of the blade and a slightly convex surface 52 on the handside of the blade. Kink 113 is formed on palm portion 46 and helps formthe convex surface 52 and concave surface 50. Kink 113 adds structuralstrength to the blade and adds to the hand comfort when the blade isworn. Furthermore, kink 113 allows for water disbursement in differentdirections, which reduces pressure build up, thus reducing flutter andhand strain.

Referring now to FIG. 4, when a user wears swim paddle 10, the userplaces hand 60 on hand side 14 of the paddle and inserts fingers 68, 70,72 and 74 through apertures 34, 36, 38 and 40, respectively, and thumb66 through notch 48. Wrist strap 62 must then be secured to hold theuser's wrist 64 to the blade. The user's palm 76 rests on palm portion46 of the blade and flanges 42 and 44 extend beyond the sides of thehand. As seen in FIGS. 6 and 7, the user may hold onto the paddle in oneof two ways, either by curling finger tips 78 through the fingerapertures to grip the blade as shown in FIG. 6 or by extending fingertips 78 such that the finger tips project outstretched as shown in FIG.7. As better shown in 5, the swept back arrangement of inter-digitalportion 55 and the swept forward orientation of finger tip portion 56permit finger tip 78 to be fully outstretched. Since the user can fullyoutstretch his or her fingers while wearing the blade, the user canmaintain the hand in a more comfortable and natural position, therebydecreasing muscle strain on the hand.

Referring back to FIGS. 2 and 4, flange portions 42 and 44 extend toeither side of the user's hand. Since the flange portions are swept backfrom the waterside of the blade towards the hand side of the blade, theflange portion extends backward relative to the rest of the blade. As aresult, as the blade is forced through the water by the user, thepattern of water turbulence (not shown) created by the swept backflanges greatly reduces the amount of flutter experienced by the blade.Elongated kinks (or folds) 110 and 111 help to form the flange portionsand add structural strength to the blade. In addition, kinks 110 and 111allow for a smoother water disbursement around the paddle, furtherreducing flutter. The reduced flutter permits the user to more easilymaintain the blade in the correct orientation as the blade is forcedthrough the water. This results in less hand strain.

The method of manufacturing the swim paddle made in accordance with thepresent invention will now be discussed. In one preferred fabricationmethod, paddle 10 is fabricated by extruding a high modulusthermoplastic into a foamed sheet of two to six thousands of an inchthick with a density of 6 to 15 pounds per cubic foot. The extrudedsheet is then thermoformed into a slightly concave geometric shape,cooled and stress-stabilized using processes well known by thoseexperienced in the art. The stress-stabilized sheet is pulled byrubber-coated rollers and cut to convenient lengths, which then passthrough a vertical cutter to cut out the paddles 10 as desired inFIG. 1. Scrap sheet material is recycled.

In another embodiment of the invention, foam is injected into a reactivemolding machine to form the paddle blade 12 in one operation. Anysuitable elastomeric polymer resin system can be molded to the desiredfoam density. Feedstocks of elastomeric polymer are injected as liquidsand allowed to foam, producing a smooth outer edge for the productpaddle.

In the preferred embodiment of the invention, the hand paddles 10 arefabricated from a commercial grade of a homopolymer polypropylene or asa copolymer of propylene and 1-20 wt. % ethylene. These polypropylenesare in the polyolefin family of plastics. They have excellent colorability, high strength, high stiffness, excellent fatigue, chemicalresistance, reasonable thermal properties, good mold ability andmoderate cost. The preferred design is molded using conventionalinjection molding with insert pins to form the four finger holes and twoslots 28 and 30, a technique well known to those skilled in the art. Thefinished paddles 10 are molded to a thickness of only 2 to 20 mm inorder to be lightweight and use less plastic. The edges or the paddleare rounded during the molding process to prevent cuts and scratches tothe swimmers hands and body. Density of the homopolymer polyethylene is0.90 and that of the copolymers just slightly higher, such that thesolid hand paddles will float in water. Copolymer paddles are slightlymore flexible and much resistant to impact cracks than the homopolymerpaddles but are slightly less rigid. Thus, they will not break ifaccidentally stepped on.

In one molding process, copolymer materials are utilized to fabricatepaddles by foaming to a density of 30 to 50 pounds per cubic foot,whereas the homopolymer solid material has a density of 56.2 pounds percubic foot. Thus, the weight of copolymer paddles can be up to one-halfless than homopolymer paddles. Adequate stiffness can be achieved bymodifying the injection molding process.

A copolymer of propylene and 20-40% by weight ethylene produces a moreflexible hand paddle with much greater toughness, durability andresistance to impact breakage than a homopolymer process.

Copolymers can be reinforced with a small amount of glass fibers,usually 5 to 20 percent, for desired stiffness. Thus, the size andgeometry of the paddles are achieved using the same molds and injectionmolding techniques as introduced above.

Copolymers of ethylene and a short-chain unsaturated aliphatichydrocarbon, such as butene-1, hexene-1, octene-1 and others that arepracticed for commercial copolymers called the family of high-densitypolyethylene (HDPE), are utilized in the molding process. Linearlow-density polyethylene mixed with a compatible copolymer of HDPE canprovide increased flexibility and a relatively tough surface.

Polyurethane polymers may also be used in the molding process. Theadvantage of the polyurethanes is that they can provide eitherthermoplastic or thermosetting products and can be used in reactivemolding to achieve desired properties. They can also be made elastomericand are tough enough to be used for auto tires moving at high speed, orthey can be formulated for elastomer properties but low strength, foruse in bed pillows. They can be also be made into rigid foams forthermal insulation. Their main disadvantage is cost.

Alternatively, paddle 10 may be formed from a thin sheet of steel, whichis stamped and cut into the desired size and geometry of the paddle. Thesemi-finished paddle is then coated by dipping in a vinyl plastisol oranother appropriate plastisol to give a surface coating to the paddlesimilar to that for plastic-coated wire grocery shopping carts. Manyother wire products utilize plastisols, e.g. wire dish drainers and coathangers. Plastisols offer wide flexibility in the selection of vinylmaterials for ease of fabrication, final properties and/or costs, due tothe unique properties of polyvinyl chloride (PVC) for being compatiblewith a variety of plasticizers and other organic materials.

For plastic-coated metal paddies the following formulation can beutilized: dispersed PVC powder in the high-boiling liquiddi-2-ethylhexylphthalate at a ratio of 3:5 or higher, liquid to polymer,to formulate a stable, free-flowing suspension of PVC (a plastisol) forcoating the hand paddle. Other plastisol formulations can be preparedusing other esters of pythalic acids, esters of adipic acid, along withepoxidized drying oils, chlorinated waxes and esters of phosphoric acid.

A thin, sheet of aluminum can be utilized instead of steel. Also, thispaddle product can be made stiffer by stamping portions of the metalsheet, cutting the portions and bending these portions to some angle ofapproximately 450 to 900 with the paddle surface, forming paddlestabilizers. When, dipped in a plastisol the resulting paddle product isreinforced for increased stiffness. The areas of the paddle, whichcontact the user's hand, may be filled with plastisol to give a smoothsurface on the hand.

Plastic powders may be used to coat the metal-based hand paddles 10instead of plastisols. A plastic coating material can be a homogeneousblend of a thermoplastic with colorants, fillers, stabilizers and otheradditives in the form of a dry, fine particle size compound similar toflour. It can be applied to the semi-finished hand paddles by firstheating the paddle and then dipping it in the powder in a fluidized bedjust long enough to create the desired coating thickness. Alternativecoating techniques usually involve electrostatic spraying or anelectrostatic bed process. The advantage of powder coating is that it isbasically a chemical coating and can be applied for very thin coatingsas in painting. For many applications of the hand paddles of thisinvention, it can provide increased performance properties to the paddleproduct.

A specific embodiment of the present invention has been disclosed;however, several variations of the disclosed embodiment could beenvisioned as within the scope of this invention. It is to be understoodthat the present invention is not limited to the embodiments describedabove, but encompasses any and all embodiments within the scope of thefollowing claims.

1. A hand paddle comprising: a. A paddle blade having a hand side and anopposite water side, a proximal end, a distal end opposite the proximalend and having a distal edge and opposite first and second lateral ends,b. A plurality of apertures formed along the distal end of the blade andseparated from the distal edge by a fingertip portion, the aperturesbeing separated from each other by inter-digital portions, the aperturesadapted and configured to receive user's fingers, c. A wrist portionformed on the proximal end of the blade, the wrist portion having awrist strap, d. A palm portion formed on the blade between the aperturesand the wrist portion, the palm portion forming a slightly concavedsurface on the waterside of the blade, e. A notch formed on the firstlateral end of the blade, the notch being adapted and configured toreceive a user's thumb, f. A first and second flange portion formed onthe first and second lateral ends, respectively, the flange portionsbeing swept back from the water side of the blade towards the hand sideof the blade, the first flange portion extending from the notch to thewrist portion, the second flange portion extending along the secondlateral end from the wrist portion to the apertures, g. Theinter-digital portions being swept back from the water side of the bladetowards the hand side of the blade, the finger tip portion being sweptforward towards the water side of the blade relative to theinter-digital portions sufficiently to permit the users fingers toextend fully through the apertures when the paddle is worn.
 2. A handpaddle comprising: a. A blade having a hand side and an opposite waterside, a proximal end, a distal end opposite the proximal end andopposite first and second lateral ends, b. A wrist portion formed on theproximal end of the blade, the wrist portion adapted and configured toretain a user's wrist when the paddle is worn, c. A finger portionformed towards the distal end of the blade, the finger portion beingadapted and configured to retain the user's fingers when the paddle isworn, d. A first and second flange portion formed on the first andsecond lateral ends, respectively, the flange portions being swept backfrom the water side of the blade towards the hand side of the blade, theflange portions extending from the wrist portion to the finger portionof the blade.
 3. The hand paddle of claim 2 wherein the finger portioncomprises a plurality of apertures formed along the distal end of thepaddle, the apertures dimensioned and configured to receive the user'sfingers when the paddle is worn.
 4. The hand paddle of claim 2 whereinthe finger portion further includes a notch on the first lateral end ofthe blade, the notch being dimensioned and configured to receive a usersthumb.
 5. The hand paddle of claim 3 wherein the distal end includes adistal edge and wherein the apertures are formed adjacent the distaledge, the apertures being separated from the distal edge by a finger tipportion adjacent the distal edge, the finger tip portion being sweptback from the water side of the blade towards the hand side of the bladesufficiently to permit the fingers to be fully extended.
 6. The handpaddle of claim 3 wherein the finger portion further includes aplurality of inter-digital portions between the apertures, theinter-digital portions being swept back from the water side of the bladetowards the hand side of the blade sufficiently to permit the fingers tobe fully extended.
 7. The hand paddle of claim 6 wherein the distal endincludes a distal edge and wherein the apertures are formed adjacent thedistal edge, the apertures being separated from the distal edge by afinger tip portion adjacent the distal edge, the finger tip portionbeing positioned relative to the rest of the blade to permit the fingersto be fully extended.
 8. The hand paddle of claim 2 wherein the bladefurther includes a palm portion positioned between the wrist portion andthe finger portion, the palm portion being slightly concave on thewaterside of the blade.
 9. The hand paddle of claim 1 wherein the paddleis made of injection molded plastic and has a density of less thanwater.
 10. The hand paddle of claim 9 wherein the paddle is made ofinjection molded foamed plastic.
 11. The hand paddle of claim 1 whereinthe paddle is made of stamped sheet metal.
 12. The hand paddle of claim11 wherein the paddle is coated with a plastic material.
 13. A method ofmanufacturing the hand paddle of claim 1 comprising the steps of firstextruding a high modulus thermoplastic into a foamed sheet of two to sixthousands of an inch thick with a density of 6 to 15 pounds per cubicfoot, then thermoforming the sheet into a slightly concave geometricshape, then cooling and stress-stabilizing the stress-stabilized sheetand then cutting out the paddles in a cutter.
 14. A method ofmanufacturing the hand paddle of claim 1 comprising the steps of forminga metal blade having the shape of the hand paddle by stamping a sheet ofmetal and then coating the metal blade with a plastic material.
 15. Thehand paddle of claim 8 wherein the blade has a plurality of kinks. 16.The hand paddle of claim 1 wherein the blade has a plurality ofelongated kinks.
 17. The hand paddle of claim 16 wherein at least one ofthe kinks extends along the palm portion of the blade.
 18. The handpaddle of claim 16 wherein at least two of the kinks separate the firstand second flange portions from the palm portion.
 19. The hand paddle ofclaim 18 wherein a kink is formed on the palm portion of the paddle, thekink forming the concave surface.